Back at the beginning of September, Elon Musk tweeted that the company would unveil its long rumored all-electric semi truck on October 26th. He noted that it was “tentatively” scheduled, leaving the door open for a date change need be. Turns out that was a good call.

In a tweet this afternoon, Elon says the Semi unveil date is now set for November 16th — a shift of about 3 weeks.

The reasoning for the rescheduling? Musk mentions two things they’re focusing on right now instead: Model 3 bottlenecks, and Puerto Rico battery production.

Yesterday morning Musk offered Tesla’s assistance in rebuilding Puerto Rico’s electric system after the devastation of Hurricane Maria left just 10% of the island with power; by the afternoon, the governor of Puerto Rico was tweeting back to say he wanted to talk about it.

As for the Model 3 bottlenecks mentioned: Tesla aimed to ship around 1,500 Model 3s in the third quarter of 2017, but disclosed on Monday that they’d ended up shipping around 260. While the company pinned the shortfall on production bottlenecks, they noted that they already “understand” the underlying issues and are “confident of addressing the manufacturing bottleneck issues in the near-term” — so, presumably, tackling those issues will be a key part of these next few weeks.